Air conditioning



Sept. 23, 1 R. B.P. CRAWFORD AIR CONDITIONING Filed Oct. 31, 1939 QHH nu al DU -U any v Patented Sept. 23, 1941 UNITED STATES PATENT OFFICE Robert B. P. Crawford, Athens, Ga. v

Application October 31, 1939, Serial No. 302,223

Claims.

This invention relates to air conditioning and is particularly directed to a method and system I of conditioning air in residences and the like in connection with radiator heating systems.

A principal purpose of the invention is the provision of an economical air conditioning system suitable for use in residences and similar buildings.

A further object of the invention is to provide an air conditioning system utilizing as fullyas possible the essential elements of a radiator heat ing system.

Another purpose of the invention is the economical utilization of available cooling water for the conditioning of air without'the use of mechanical refrigeration.

In general, the invention comprises an air conditioning system in which the moisture content of the air is reduced by direct contact with a hygroscopic liquid. This air is then cooled, preferably adiabatically or substantially so, by evaporative cooling contact with water from a suitable source of supply such as well water or city water. The water from the adiabatic cooling operation is utilized for direct cooling of the conditioned space. A part of this water may advantageously be utilized for cooling the hygroscopic liquid, either while the hygroscopic liquid is being contacted with the air, or by passing the hygroscopic liquid in heat exchange relation with the water while the water is subjected to the evaporative cooling effect of a stream of air, or both.

The hygroscopic liquid is preferably maintained at a suitable concentration by evaporation of water therefrom in a boiler, particularly in a boiler suitable for use in cold weather in supplying heated fluid, for example, hot water or steam, to heating radiators in the conditioned space. The radiators are likewise preferably utilized in warm or humid weather for the direct cooling of the conditioned space by means of the water from the adiabatic air cooling zone.

The invention will be more particularly described for the purpose of illustration with reference to the accompanying drawing which is a semi-diagrammatic representation of an air con- In the particular form of the system illustrated in the drawing, the conditioning units include adehumidifier I, an air cooling unit 2, and 'a hygroscopic liquid cooling unit 3.

An air stream to be supplied to the conditioned space in floors B and C is forced by fan 4 into dehumidifier l where it is contacted with a hygroscopic liquid such as a solution of calcium chloride, sprayed from spray members 5 downwardlyover the exterior of extended surface coils 6, counter-current to the air stream.

On leaving the dehumidifier the air passes through filter I and spray eliminator 8 and thence to the cooling unit where it is brought into contact with an extended surface of water from any suitable source at sprays 9.

A portion of the excesscooling water, which is Q collected in sump i0, is passed through extended surface coils G where it removes from the hygroscopic liquid heat absorbed by the liquid from the air. From coils 6 the water is sprayed through sprays ll over the exterior of extended surface coils 12 through which hygroscopic liquid is circulated from sump l3 to sprays J by means of pump H. The evaporative cooling effect of the water in contact with a stream of air supplied by fan l5 removes heat from the hygro scopic liquid coming from sump l3 andfrom the concentrator through pipe l6.

The cool air from cooling unit 2 passes through suitable conduits ll, controlled by dampers I8, into conditioned spaces B and C. A portion of the cooled water collected in sump I0 is .caused to flow through direct cooling radiators l9 in'the conditioned spaces. conditioned spaces is circulated over radiators I! by means of fans 20. After passing through the radiators I! the water is sent to waste.

A suitable proportion of the hygroscopic liquid from sump I3 is .passed to boiler 2| through heat exchanger 22 counter-currently to the hot conditioning-system embodying the principles ofthe centrated liquid leaving the separating pan 28. Preferably, the boiler is the same as is used in cold weather for heating and circulating hot fluid to radiators I! through conduits 23 and 24, When the system is used for heating valves 30, SI, 32 and 33 are closed and valves 34 and 35 are opened.

The concentration of the hygroscopic liquid leaving the boiler is maintained at the desired point by means of thermostat 25 which regulates fuel burner 26 so as to maintain the liquid in the boiler at a boiling point corresponding to th desired concentration.

The concentrated liquid and vapor pass Preferably, the air in the through conduit 21 to separating pan 28 wherethe vapor is released. The liquid flows from the pan through conduit l6 to the heat exchanger 22 and thence to the dehumidifier recirculating system through pump H. The concentrated liquid is carried to separating pan 28 by the vapor lift effect of the vapor generated in the boiler. If desired the concentrated liquid outlet pipe 21 may be connected directly to the intake of pump it andthe vapor generated in the boiler may then be exhausted directly to the atmosphere.

It will be obvious that the operation of the system may readily be controlled by means of humidostats and thermostats positioned at suitable points in the conditioned air conduits and in the conditioned spaces and such controls,:

which may be of a type well known in the art, are not shown or described herein.

I claim: 1. A method of conditioning air which com prises reducing ,the moisture content of the air by direct contact with a hygroscopic liquid, thereafter subjecting the air to direct contact with an extended surface of water in an amount in excess of the amount of water evaporated during said,

contact, passing a portion or said water into heat exchange relation with said hygroscopic liquid.

supplying said air to the space to be conditioned and bringinga portion of said water into heat exchange relation with the air in said space.

2. A method of conditioning air which comprises reducing the moisture content of the air by direct contact with a hygroscopic liquid, thereafter subjecting the air to direct contact with an extended surface of water in an amount in excess of the amount of water evaporated during said contact, passing a portion of said water into heat exchange relation with said hygroscopic liquid while the hygroscopic liquid is being contacted with the air, supplying said air to the space to be conditioned and bringing a portion of said water into heat exchange relation with the air in said space.

3. A method 0! conditioning air which com-.

prises reducing the moisture content oi the air by direct contact with a hygroscopic liquid, thereafter subjecting the air to direct contact with an extended surface of water in an amount in excess of the amount or water evaporated during said contact, passing a portion or said water into heat exchange relation with said hygroscopic liquid ,while subjecting said water to evaporative cooling contact with a stream of air, supplying said air to the space to be conditioned and bringing a portionot said water into heat exchange relation with the air in said space.

4. A method of conditioning air which comprises reducing the moisture content of the air by direct contact with a hygroscopic liquid, thereafter subjecting the air to direct contact with an extended surface of 'water in an amount in excess of the amount of water'evaporated during said contact, passing a portion of said water into heat exchange relation with said hygroscopic liquid while the hygroscopic liquid is being contacted with the air and thereafter passing said water into heat exchange relation with the hygroscopic liquid while subjecting said water to evaporative cooling contact with a stream of air. supplyin said air to the space to be conditioned and bringing a portion of said water into heat exchange relation with the air in said space.

5. Air conditioning system for residences and the like comprising means for bringing a stream or air successively into contact with a hygroscopic liquid and an extended surface water stream. means for bringing at least a portion of the water which has been contacted with the air stream into heat exchange relation with the hygroscopic liquid, heat exchange elements positioned in the space to be conditioned, and means for supplying at least a portion of the water which has been contacted with the air stream to said heat exchange elements.

ROBERT B. P. 

